fix(grpc): Read method from handler_call_details for grpcio >= 1.76 compat

[yeung108]

Summary

Fixes sync ServerInterceptor to work with grpcio >= 1.76 by reading the method name from handler_call_details.method instead of context._rpc_event.call_details.method.

Problem

grpcio 1.76 introduced registered method handlers (add_registered_method_handlers) which resolve RPC methods at the C-core level. For these registered methods, context._rpc_event.call_details.method returns an empty string, causing Sentry tracing to silently fail (no transactions, no spans, no trace IDs in logs).

Solution

Capture handler_call_details.method directly in the closure scope before defining the behavior function. This approach:

1. Fixes grpcio >= 1.76 compatibility - handler_call_details.method is always populated by grpcio's _find_method_handler
2. Avoids race conditions - No shared instance state; each call creates its own closure with captured values
3. Maintains backward compatibility - Custom find_name parameter still works

Why Closure Capture Instead of Instance State?

The gRPC sync server uses a ThreadPoolExecutor where multiple threads share the same ServerInterceptor instance. Storing state as self._handler_call_details would create a race condition where one thread could overwrite the value before another thread's behavior closure reads it.

Fixes #5520

[github-actions]

Semver Impact of This PR

🟢 Patch (bug fixes)

📋 Changelog Preview

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Bug Fixes 🐛

Openai

• Avoid consuming iterables passed to the Completions API by alexander-alderman-webb in #5489
• Avoid consuming iterables passed to the Embeddings API by alexander-alderman-webb in #5491

Other

• (anthropic) Fix token accounting by shellmayr in #5490
• (google-genai) Remove agent spans for simple requests by alexander-alderman-webb in #5443

• (grpc) Read method from handler_call_details for grpcio >= 1.76 compat by yeung108 in #5521

Documentation 📚

• New integration guide by alexander-alderman-webb in #5476

Internal Changes 🔧

• (agents) Add sentry skills to be used by warden in CI reviews by ericapisani in #5485
• (ai) Add configuration for dotagents by ericapisani in #5480
• (github) Add warden configuration by ericapisani in #5484
• (openai-agents) Expect new tool fields by alexander-alderman-webb in #5471
• (repo) Add .serena to .gitignore by ericapisani in #5464
• 🤖 Update test matrix with new releases (02/19) by github-actions in #5483
• 🤖 Update test matrix with new releases (02/18) by github-actions in #5475

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[sentrivana]

Thanks @yeung108, looks good to me.